Al-Mashikhi S A, Nakai S
Department of Food Science, University of British Columbia, Vancouver, Canada.
J Dairy Sci. 1987 Dec;70(12):2486-92. doi: 10.3168/jds.S0022-0302(87)80315-6.
Whey is a suitable source of immunoglobulins and lactoferrin to enrich infant formulas. Gel filtration on Sephacryl S-300 and on Fractogel TSK HW-55 was used to isolate immunoglobulins from colostral whey, acid whey, and Cheddar cheese whey. The SDS-PAGE and immunoelectrophoresis techniques indicated that the purity of the fractions from fractionation on Sephacryl S-300 was better than that by fractionation on TSK HW-55 column. Biological activity of fractions from the Sephacryl S-300 column as assessed by immunochemical analysis was 99, 83.3, and 92% for colostral, acid, and sweet wheys. The well-proven antimicrobial agent, lactoferrin, was isolated from sweet whey by heparin-attached Sepharose. Lactoferrin selectively adsorbed to the column was subsequently eluted with 5 mM Veronal-HCl containing .5 M NaCl, pH 7.4. Purity of the isolated protein was confirmed by SDS-PAGE and immunoelectrophoresis.
乳清是用于强化婴儿配方奶粉的免疫球蛋白和乳铁蛋白的合适来源。使用Sephacryl S - 300和Fractogel TSK HW - 55进行凝胶过滤,从初乳乳清、酸乳清和切达干酪乳清中分离免疫球蛋白。SDS - PAGE和免疫电泳技术表明,在Sephacryl S - 300上分级分离得到的级分纯度优于在TSK HW - 55柱上分级分离得到的级分。通过免疫化学分析评估,Sephacryl S - 300柱上的初乳、酸乳清和甜乳清级分的生物活性分别为99%、83.3%和92%。通过肝素偶联琼脂糖从甜乳清中分离出了经过充分验证的抗菌剂乳铁蛋白。选择性吸附到柱上的乳铁蛋白随后用含0.5 M NaCl、pH 7.4的5 mM巴比妥 - HCl洗脱。通过SDS - PAGE和免疫电泳确认了分离出的蛋白质的纯度。